A question about Blender's camera model

I’m gettin more and more familiar with Blender, and it’s interface, and really started to appreciate it,

I have anyway one question about the camera model. I can choose, for setting the camere field of view, not directly the angle, but I must set focal view. This is a good thing, because it is final frame independent, etc, but… focal leght gets a sense when combined with a precise format for the CCD or similar, so my question is: what is Blender’s camera focal lenght referred to?
From what I see, I’d say it’s relative to a 35mm still camera, so 24 mm is a wide angle lens, and 50 mm is the “normal” lens, etc…

Am I right?


Yes, you’re right, it an approximation of 35mm.


Have a look at this.

The camera is at the bottom, the red angle is our desired FOV (field of view), and the length of the green line is what the Lens parameter represents in Blender. Therefore, the formula to calulcate Lens when we know FOV:

Lens = 16 / tan(FOV / 2)

(taken from Blender 3D: Noob to Pro/Looking All Around - Panorama Settings)